PEP therapy is used primarily in pulmonary secretion removal. Devices used to perform PEP therapy provide positive pressure during expiration. The patient or user exhales against a fixed orifice resistor and generates a pressure ranging approximately from 10-20 cm H2O. The resistance orifice is an important consideration and frequently is initially set by a physician, veterinarian, or a skilled practitioner in the art. An orifice that is too large may result in a short exhalation that will not produce proper expiratory pressure. An orifice that is too small may result in a longer expiratory phase that raises the pressure above approximately 20 cm H2O and ultimately increases the work of breathing.
During the exhalation phase of PEP therapy, the airway is splinted open by the pressure. This causes the movement of secretions from the peripheral airways into the larger airways where they can be expelled. PEP therapy usually lasts for about 10-20 minutes and is performed as required, generally 1-4 times per day. Typically, the patient performs 10-20 PEP breaths, removes the device from their mouth and follows this with a forceful exhalation. This final exhalation triggers a cough that loosens secretions.
Studies indicate that PEP therapy dilates the airways and improves the distribution of ventilation, resulting in a better deposition of an inhaled substance, such as, but not limited to, a medicine or remedy. As used herein, the term “aerosol delivery apparatus” means any apparatus capable of producing and/or delivering a substance, such as, but not limited to, a medicine, in a form suitable for inhalation by a patient and includes, without limitation, an aerosol holding chamber, nebulizer, spacer with integrated actuator, a dry powder inhaler, and a metered dose inhaler.